package com.lagou.client;


import com.lagou.handler.UserClientHandler;
import com.lagou.service.JSONSerializer;
import com.lagou.service.RpcDecoder;
import com.lagou.service.RpcEncoder;
import com.lagou.service.RpcRequest;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.UUID;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * 消费者
 */
public class RPCConsumer {

    //1.创建一个线程池对象，它要处理我们自定义事件
    private static ExecutorService executorService = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());

    //2.声明一个自定义事件处理器 UserClientHandler
    private static UserClientHandler userClientHandler;
    //3.编写方法初始化客户端 （创建连接池，创建bootstrap 设置bootstrap 连接服务器）
    public static void initClient() throws InterruptedException {
        //1.初始化UserClientHandler
        userClientHandler = new UserClientHandler();
        //2.创建连接池对象
        NioEventLoopGroup group = new NioEventLoopGroup();
        Bootstrap bootstrap = new Bootstrap();
        bootstrap.group(group)
                .channel(NioSocketChannel.class)
                .option(ChannelOption.TCP_NODELAY,true)
                .handler(new ChannelInitializer<SocketChannel>() {
                    protected void initChannel(SocketChannel socketChannel) throws Exception {
                        //1.获取管道对象
                        ChannelPipeline pipeline = socketChannel.pipeline();
                        pipeline.addLast(new RpcEncoder(RpcRequest.class, new JSONSerializer()));
                        pipeline.addLast(new StringDecoder());
                        pipeline.addLast(userClientHandler);

                    }
                });
        //5. 连接服务端
        bootstrap.connect("127.0.0.1",8999).sync();
    }
    //4.编写一个方法，使用JDK的动态代理创建对象
    //serviceClass 接口类型，根据哪个接口生成自雷代理对象；providerParam："UserService#sayHello#"
    public static Object createProxy(final Class<?> serviceClass, final String providerParam){
        return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),
                new Class[]{serviceClass}, new InvocationHandler() {
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                        //1.初始化客户端client
                        if(userClientHandler == null){
                            initClient();
                        }
                        //封装RpcRequest
                        RpcRequest rpcRequest = new RpcRequest();
                        String className = providerParam.substring(0,providerParam.indexOf("#"));
                        rpcRequest.setClassName(className);
                        rpcRequest.setMethodName(method.getName());
                        rpcRequest.setParameters(args);
                        rpcRequest.setParameterTypes(method.getParameterTypes());
                        rpcRequest.setRequestId(UUID.randomUUID().toString());
                        //2.给UserClientHandler设置param参数
                        //userClientHandler.setParam(providerParam+args[0]);
                        userClientHandler.setRpcRequest(rpcRequest);
                        //3.使用线程池，开启一个线程处理call()写操作，并返回结果
                        Object result = executorService.submit(userClientHandler).get();
                        //4.return结果
                        return result;
                    }
                });
    }
}
